docs: def zoom_in(self, action=None, channel=0):
          """
          Params:
              action              - start or stop
              channel             - channel number
  
          The magic of zoom in 1x, 2x etc. is the timer between the cmd
          'start' and cmd 'stop'. My suggestion for start/stop cmd is 0.5 sec
          """
  
          ret = self.command(
              'ptz.cgi?action={0}&channel={1}&code=ZoomTele&arg1=0'
              '&arg2=0&arg3=0'.format(action, channel)
          )
          return ret.content.decode('utf-8')